- #1
nineteen
- 68
- 12
Homework Statement
In an organic compound "A" only C,H and O is present. 1.22g of A is completely burned and it gives 0.84g of CO2 and 0.54g of H2O. If the relative molecular mass of "A" is 123. Find the molecular formula of A.
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I have showed my attempt at solving this problem, but I think it is wrong. Please help me out here. After what I have done last, there are only a few more steps to find the empirical formula and then the molecular formula itself, but I think what I have done is wrong. Please try and correct me, I'd appreciate it a lot.
2. Homework Equations
no. of moles = Mass/Molar mass
n of the molecular formula = Molar mass/ Formula mass of the empirical formula
(I guess that those are the only equations)
n of the molecular formula = Molar mass/ Formula mass of the empirical formula
(I guess that those are the only equations)
The Attempt at a Solution
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Mass of C in CO2 produced: (12/44) x 0.84g = 0.22g
Mass of O in CO2 produced: (32/44) x 0.84g = 0.61g
Mass of H in H2O produced: (2/18) x 0.54g = 0.06g
Mass of O in H2O produced : (16/18) x 0.54g = 0.48g
Total masses;
C = 0.22g
O = 1.09g
H = 0.06g
Molar ratios of elements;
C ----> (0.22/12) = 0.01
H ----> (0.06/1) = 0.06
O ----> (1.09/16) = 0.06
Dividing all by the smallest value;
C ----> 0.01/0.01 = 1
H ----> 0.06/0.01 = 6
O ----> 0.06/0.01 = 6
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